Agilent Technologies 34970A, Руководство по обслуживанию

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Self-Tests
A complete self-test performs the following tests. A failing test is
indicated by the test number and description in the display.
601
Front panel not responding
The main CPU A1U205 attempts to
establish serial communications with the front panel processor A2U1.
During this test, A2U1 turns on all display segments. Communication
must function in both directions for this test to pass. If this error
is detected during power-up self-test, the instrument will beep.
This error is only readable from the remote interface.
602 RAM read/write failed
This test writes and reads a 55
η
and AA
η
checkerboard pattern to each address of RAM. Any incorrect
readback will cause a test failure. This error is only readable from the
remote interface.
603
A / D sync stuck
The main CPU issues an A/ D sync pulse to
A1U209 and A1U205 to latch the value in the ADC slope counters.
A failure is detected when a sync interrupt is not recognized and a
subsequent time-out occurs.
604
A / D slope convergence failed
The input amplifier is configured
to the measure zero (MZ) state in the 10 V range. This test checks
whether the ADC integrator produces nominally the same number of
positive and negative slope decisions (
±
10%) during a 20 ms interval.
605
Cannot calibrate rundown gain
This test checks the nominal
gain between the integrating ADC and the A1U205 on-chip ADC.
This error is reported if the procedure can not run to completion due
to a hardware failure.
606 Rundown gain out of range
This test checks the nominal gain
between the integrating ADC and the A1U205 on-chip ADC. The
nominal gain is check to ± 10% tolerance.
607 Rundown too noisy
This test checks the gain repeatability
between the integrating ADC and the A1U205 on-chip ADC. The gain
test (606) is performed eight times. Gain noise must be less than ± 64
LSB’s of the A1U205 on-chip ADC.
Chapter 6 Service
Self-Test Procedures
168